You may not be the only one she’s thinking about during solo sex: 48 percent of women fantasize about a sexual situation with an ex during masturbation, according to a recent survey of 4,500 people by sex toy retailer Lovehoney.

The women surveyed also said they fantasize about erotica, a sexual situation involving BDSM, and roleplay during masturbation, too.

Good news is, 60 percent of women reported that they their top fantasy involves a situation with their current partner.

But what if she’s not thinking about you? Should you be concerned?

To be fair, nearly 60 percent of guys also admitted to fantasizing about their ex during masturbation. And that’s okay: Masturbation is one of the best things someone can do for his or her sex life, says sex and marriage therapist Moushumi Ghose, author of Classic Positions Reinvented.

“When you masturbate, the message that you send is that your pleasure is important to you,” says Ghose. “If you want a relationship based on honesty and integrity, then to talk about what turns you on and how to get you off is a great place to begin.”

If you really want your relationship to grow, mutual masturbation can be a great way to connect, she says: “Sharing this secret side of you can be very powerful.”

But no guy really wants his girlfriend or wife fantasizing about another man in bed—so when do her secrets become something to worry about?

“Fantasizing about an ex is not really a problem at all,” Ghose explains. “Our fantasies are often ways in which we work out some of the things we experience in our lives. It’s a release and catharsis, so fantasizing about the ex in and of itself is not an issue at all.”

Obviously, there’s no way of knowing what she fantasizes about unless you ask her. Even then, if there are no problems between you and her in and outside of the bedroom, just let her do her thing.

What actually matters is whether your partner expresses interest in her ex outwardly in other ways—say, constantly communicating with her ex or dropping his name in conversation.

“If she is overly obsessed with these fantasies, it might also mean she is no over her ex,” says Ghose.

If you think that might be the case, talk to her about it. But if things are going better than ever, then don’t sweat it—remember, a majority of women say their current partner is the one they think about, anyway.